Enabling Direct3D on standard Win7 drivers - expert needed

I've been having issues with my laptop for quite some time and it mostly stemmed from an issue with my GPU. The GPU kept throttling its voltages when it was switching from 2D rendering to 3D rendering and it would cause the laptop to crash. My workaround solution for this was to download Rivatuner and force the GPU to be in 3D performance around the clock. This has been how I've kept my laptop up and running and gaming for the last year and a half or so.

Lately I've encountered a new problem with the computing crashing to a black screen again, despite updating graphics card drivers, reformatting, checking my DC input to see if it was shorting itself on the cables to the monitor, as well as disabling my undervolt I had on my CPU and buying a new power adapter. This all has no fixed whatever issue is going on with my laptop.

Now, upon finally reformatting my computer and some trial and error I have found that if I simply don't upgrade my graphics card drivers from the standard ones installed with Win7 my computer won't black screen on me. The only downfall to this issue is that by not updating my graphics card drivers I cannot for the life of me figure out if its possible to enable Direct3D or not.

I'll tell you what I have done to try to enable it:

I've tried downloading all the optional SDK DirectX software.
I've tried enabling Direct3D through the registry, but there are no values for anything pertaining to Direct3D.
I've tried enabling it through the Display Properties in Windows 7, through desk.cpl and there are no options for Hardware Acceleration, probably because I don't have any real drivers for my GPU.

Those of you who feel my computer model and such are important I'll give you the info here:

Gateway P7811-FX
nVidia GeForce 9800M GTS

I must make a point that using the official nVidia drivers 258.xx from the nVidia website or using more updated drivers and modifying the INF makes no difference to how the laptop crashes, it still does, no matter what. The only thing that seems to keep it from crashing with the drivers updated on it is simply running it off the battery, strangely enough having it run on the AC adapter makes it crash.

Any insight on this or experiments you think might help me out, or anyone who knows if in my situation you can enable Direct3D Acceleration would be greatly appreciated. I bought this laptop when it was retailing for $1200 and I'm still paying the student loan off for it, would really break my heart if I can't salvage it. I'm no professional in the field, but I'd like to believe I've done every possible thing to try and fix this issue.